Sound scattering of double concentric elastic spherical shell with multilayered medium cloak

A three-dimensional spherical acoustic cloak with homogeneous isotropic materials is designed based on the effective medium approximated theory. The analytical solution of the scattering field from underwater double concentric elastic spherical shell covered with multilayered medium is formulated using the partial waves series expressions (PWSE). The acoustic scattered fields and backscattering form functions of the spherical shells covered and uncovered with multilayered medium have been computed. It could be demonstrated that the propagating direction of the acoustic wave could be changed in the multilayered medium. At low frequency range, the cloak performs quite well to hide the objects under the illumination by an acoustic beam. The present study may be helpful to design acoustic cloak for the acoustic waves in the different incidence directions.